Effect of high temperature frying on the structure and properties of potato starch

In this paper, the physicochemical properties of potato starch fried at different temperatures were investigated. Changes of the morphological characteristics of starch granules, crystal structure, pasting properties, the transparency and freeze-thaw stability of starch were monitored by using SEM, polarizing microscope, XRD and Brabender Viscograph. The results showed that the morphological characteristics of starch granules changed significantly. As the frying temperature increased, some granules appeared to be sunken, expanded and ruptured. The polarized crosses of the frying starch became more blurred, and eventually disappeared. The crystal structure of starch was destroyed, changes of the structure of the frying starch at 180℃ was the most significantly, which explained that the sample was the most suitable for the digestion and absorption. The viscosity of the samples gradually decreased with the frying temperature increasing. Compared with the native starch, the peak viscosity of samples decreased. The transparency and freeze-thaw stability of the frying starch were lower than that of native starch, fried starchy food was not suitable for freezing.